I'm guessing this has been covered in some other thread, but I'll post here for my own sake when I need to buy some touch up paint.
Portimao Blue color code is C31. Here are some links to retailers who sell it. I can't vouch for accuracy or quality.
https://scratcheshappen.com/shop/tou...imao-blue-c31/
https://www.paintscratch.com/touch_u...allic-C31.html
https://touchupdirect.com/shop/touch...-metallic-c31/